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arXiv · 1307.8160

Three-cluster dynamics within an ab initio framework

S. Quaglioni·C. Romero-Redondo·P. Navrátil
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Abstract

We introduce a fully antisymmetrized treatment of three-cluster dynamics within the ab initio framework of the no-core shell model/resonating-group method (NCSM/RGM). Energy-independent non-local interactions among the three nuclear fragments are obtained from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with bound-state boundary conditions by means of the hyperspherical-harmonic method on a Lagrange mesh. We discuss the formalism in detail and give algebraic expressions for systems of two single nucleons plus a nucleus. Using a soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we apply the method to an $^4$He+$n+n$ description of $^6$He and compare the results to experiment and to a six-body diagonalization of the Hamiltonian performed within the harmonic-oscillator expansions of the NCSM. Differences between the two calculations provide a measure of core ($^4$He) polarization effects.

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S. Quaglioni, C. Romero-Redondo, P. Navrátil. 2013-07-30. Three-cluster dynamics within an ab initio framework. https://doi.org/10.1103/physrevc.88.034320

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